import { afterEach, describe, expect, it, type Mock, spyOn, vi } from "bun:test";
import { createHash } from "node:crypto";
import * as nodeFs from "node:fs";
import * as fs from "node:fs/promises";
import * as os from "node:os";
import * as path from "node:path";
import * as pluginCli from "@oh-my-pi/pi-coding-agent/cli/plugin-cli";
import * as updateCli from "@oh-my-pi/pi-coding-agent/cli/update-cli";
import {
	buildBunInstallArgs,
	buildHomebrewUpdateArgs,
	buildMiseForceInstallArgs,
	buildMiseUpgradeArgs,
	buildNpmInstallArgs,
	buildRenameCleanupPackages,
	downloadVerifiedBinary,
	isMuslLinuxForTest,
	migrateRenamedInstall,
	parseUpdateArgs,
	pruneBunInstallCache,
	type ReleaseInfo,
	type RenameMigrationSteps,
	replaceBinaryForUpdate,
	resolveBunGlobalNodeModulesDirFromLocations,
	resolveReleaseBinaryAsset,
	resolveReleaseDist,
	resolveReleaseRename,
	resolveUpdateMethodForTest,
	resolveUpdateTargetFromPathForTest,
	shouldForceBinaryUpdate,
	sweepStaleUpdateArtifacts,
	updateViaBinaryAt,
	updateViaShimTakeover,
} from "@oh-my-pi/pi-coding-agent/cli/update-cli";
import Update from "@oh-my-pi/pi-coding-agent/commands/update";
import { removeWithRetries } from "@oh-my-pi/pi-utils";
import type { CliConfig } from "@oh-my-pi/pi-utils/cli";
import { getThemeByName, setThemeInstance } from "../src/modes/theme/theme";

const tempDirs: string[] = [];

async function makeTempDir(): Promise<string> {
	const dir = await fs.mkdtemp(path.join(os.tmpdir(), "omp-update-test-"));
	tempDirs.push(dir);
	return dir;
}

afterEach(async () => {
	vi.restoreAllMocks();

	await Promise.all(tempDirs.splice(0).map(dir => removeWithRetries(dir)));
});
const TEST_CONFIG: CliConfig = {
	bin: "omp",
	version: "0.0.0-test",
	commands: new Map(),
};

describe("update command plugin dispatch", () => {
	it("routes -l to plugin upgrade instead of the app updater", async () => {
		const pluginSpy = spyOn(pluginCli, "runPluginCommand").mockResolvedValue(undefined);
		const updateSpy = spyOn(updateCli, "runUpdateCommand").mockResolvedValue(undefined);

		const command = new Update(["-l"], TEST_CONFIG);
		await command.run();

		expect(pluginSpy).toHaveBeenCalledWith({ action: "upgrade", args: [], flags: {} });
		expect(updateSpy).not.toHaveBeenCalled();
	});

	it("keeps normal update flags on the app updater path", async () => {
		const pluginSpy = spyOn(pluginCli, "runPluginCommand").mockResolvedValue(undefined);
		const updateSpy = spyOn(updateCli, "runUpdateCommand").mockResolvedValue(undefined);

		const command = new Update(["--check", "--force"], TEST_CONFIG);
		await command.run();

		expect(updateSpy).toHaveBeenCalledWith({ force: true, check: true });
		expect(pluginSpy).not.toHaveBeenCalled();
	});
});

describe("parseUpdateArgs", () => {
	it("preserves the legacy plugin update shorthand", () => {
		expect(parseUpdateArgs(["update", "-l"])).toEqual({ force: false, check: false, plugins: true });
	});
});

describe("update-cli libc detection", () => {
	it("does not mistake an installed musl loader for a glibc host", () => {
		expect(
			isMuslLinuxForTest({
				platform: "linux",
				alpineRelease: false,
				lddOutput: "ldd (Ubuntu GLIBC 2.39-0ubuntu8.7) 2.39",
			}),
		).toBe(false);
	});

	it("recognizes a musl host from ldd output", () => {
		expect(
			isMuslLinuxForTest({
				platform: "linux",
				alpineRelease: false,
				lddOutput: "musl libc (x86_64)",
			}),
		).toBe(true);
	});
});

describe("update-cli install target detection", () => {
	it("leaves Nix store installations under Nix management", () => {
		const method = resolveUpdateMethodForTest(
			"/nix/store/0123456789-omp-17.2.15/bin/omp",
			"/nix/store/9876543210-bun-1.3.14/bin",
		);

		expect(method).toBe("nix");
	});

	it("uses bun update when prioritized omp is inside bun global bin", () => {
		const method = resolveUpdateMethodForTest("/Users/test/.bun/bin/omp", "/Users/test/.bun/bin");

		expect(method).toBe("bun");
	});

	it("uses npm update when prioritized omp is inside an npm global bin", () => {
		const method = resolveUpdateMethodForTest("/Users/test/.npm-global/bin/omp", undefined, {
			npmBinDir: "/Users/test/.npm-global/bin",
		});

		expect(method).toBe("npm");
	});

	it("uses npm update for Windows npm command shims even when no package-manager bin dirs were detected", () => {
		const method = resolveUpdateMethodForTest("C:\\Users\\test\\AppData\\Roaming\\npm\\omp.cmd", undefined);

		expect(method).toBe("npm");
	});

	it("uses binary update when a plain file in the npm global bin dir is the standalone binary, not an npm symlink", () => {
		// Regression: with `npm prefix -g` pointed at the installer's default
		// (~/.local), directory containment alone misclassified the standalone
		// binary as npm-managed, so `npm install -g` failed with EEXIST refusing
		// to overwrite the existing executable.
		const method = resolveUpdateMethodForTest("/home/u/.local/bin/omp", undefined, {
			npmBinDir: "/home/u/.local/bin",
			ompIsRegularFile: true,
		});

		expect(method).toBe("binary");
	});

	it("uses binary update when a plain file in the bun global bin dir is the standalone binary", () => {
		const method = resolveUpdateMethodForTest("/home/u/.local/bin/omp", "/home/u/.local/bin", {
			ompIsRegularFile: true,
		});

		expect(method).toBe("binary");
	});

	it("keeps bun update for regular-file entries in the bun global bin dir on Windows, where bun writes .exe shims", () => {
		// On Windows a bun-managed global install is a regular-file .exe
		// launcher, not a symlink, so the standalone-binary override must not
		// apply there — it would clobber the shim with a raw binary. Paths use
		// forward slashes so the lexical containment check works on the POSIX
		// host running this suite; the platform gate is what is under test.
		const platformDescriptor = Object.getOwnPropertyDescriptor(process, "platform");
		if (!platformDescriptor) throw new Error("process.platform descriptor missing");
		Object.defineProperty(process, "platform", { ...platformDescriptor, value: "win32" });
		try {
			const method = resolveUpdateMethodForTest("C:/Users/test/.bun/bin/omp.exe", "C:/Users/test/.bun/bin", {
				ompIsRegularFile: true,
			});

			expect(method).toBe("bun");
		} finally {
			Object.defineProperty(process, "platform", platformDescriptor);
		}
	});

	it("still uses npm update when the npm global bin entry is a package-manager symlink, not a plain file", () => {
		const method = resolveUpdateMethodForTest("/home/u/.local/bin/omp", undefined, {
			npmBinDir: "/home/u/.local/bin",
			ompIsRegularFile: false,
		});

		expect(method).toBe("npm");
	});

	it("updates the resolved standalone binary behind a foreign npm-bin alias", async () => {
		const dir = await makeTempDir();
		const npmBinDir = path.join(dir, ".npm-global", "bin");
		const standalonePath = path.join(dir, ".local", "bin", "omp");
		const aliasPath = path.join(npmBinDir, "omp");
		await fs.mkdir(npmBinDir, { recursive: true });
		await fs.mkdir(path.dirname(standalonePath), { recursive: true });
		await Bun.write(standalonePath, "binary");
		await fs.symlink(standalonePath, aliasPath);

		const target = resolveUpdateTargetFromPathForTest(aliasPath, undefined, {
			allowPackageManagers: true,
			npmBinDir,
		});

		expect(target).toEqual({ method: "binary", path: standalonePath, replacesSymlink: false });
		expect(await fs.readlink(aliasPath)).toBe(standalonePath);
	});

	it("uses npm update when the bin symlink resolves into npm's global install tree", () => {
		const method = resolveUpdateMethodForTest("/home/u/.npm-global/bin/omp", undefined, {
			npmBinDir: "/home/u/.npm-global/bin",
			ompRealpath: "/home/u/.npm-global/lib/node_modules/@oh-my-pi/pi-coding-agent/dist/cli.js",
		});

		expect(method).toBe("npm");
	});

	it("uses binary update when the bun global bin entry is a foreign alias symlink", () => {
		const method = resolveUpdateMethodForTest("/home/u/.bun/bin/omp", "/home/u/.bun/bin", {
			ompRealpath: "/home/u/.local/bin/omp",
		});

		expect(method).toBe("binary");
	});

	it("uses bun update when the bin symlink resolves into bun's global install tree", () => {
		const method = resolveUpdateMethodForTest("/home/u/.bun/bin/omp", "/home/u/.bun/bin", {
			ompRealpath: "/home/u/.bun/install/global/node_modules/@oh-my-pi/pi-coding-agent/dist/cli.js",
		});

		expect(method).toBe("bun");
	});

	it("uses binary update when prioritized omp is outside bun global bin", () => {
		const method = resolveUpdateMethodForTest("/Users/test/.local/bin/omp", "/Users/test/.bun/bin");

		expect(method).toBe("binary");
	});

	it("uses binary update when bun global bin cannot be resolved", () => {
		const method = resolveUpdateMethodForTest("/Users/test/.local/bin/omp", undefined);

		expect(method).toBe("binary");
	});

	it("uses Homebrew update when prioritized omp resolves into the Homebrew formula", async () => {
		const dir = await makeTempDir();
		const prefix = path.join(dir, "opt", "omp");
		const linkedBin = path.join(dir, "bin");
		await fs.mkdir(path.join(prefix, "bin"), { recursive: true });
		await fs.mkdir(linkedBin, { recursive: true });
		await Bun.write(path.join(prefix, "bin", "omp"), "binary");
		await fs.symlink(path.join(prefix, "bin", "omp"), path.join(linkedBin, "omp"));

		const method = resolveUpdateMethodForTest(path.join(linkedBin, "omp"), "/Users/test/.bun/bin", {
			homebrewPrefix: prefix,
		});

		expect(method).toBe("brew");
	});

	it("uses mise update when prioritized omp is in an active mise bin path", () => {
		const method = resolveUpdateMethodForTest(
			"/Users/test/.local/share/mise/installs/github-can1357-oh-my-pi/latest/bin/omp",
			undefined,
			{
				miseBinDirs: ["/Users/test/.local/share/mise/installs/github-can1357-oh-my-pi/latest/bin"],
			},
		);

		expect(method).toBe("mise");
	});

	it("uses mise update when prioritized omp is a mise shim", () => {
		const method = resolveUpdateMethodForTest("/Users/test/.local/share/mise/shims/omp", undefined, {
			miseDataDir: "/Users/test/.local/share/mise",
		});

		expect(method).toBe("mise");
	});
});

describe("update-cli package manager commands", () => {
	it("targets the Homebrew tap formula and switches to reinstall for forced updates", () => {
		expect(buildHomebrewUpdateArgs(false)).toEqual(["upgrade", "can1357/tap/omp"]);
		expect(buildHomebrewUpdateArgs(true)).toEqual(["reinstall", "can1357/tap/omp"]);
	});

	it("targets the mise GitHub backend tool and force-reinstalls the checked version when requested", () => {
		expect(buildMiseUpgradeArgs()).toEqual(["upgrade", "github:can1357/oh-my-pi", "--bump"]);
		expect(buildMiseForceInstallArgs("15.10.5")).toEqual(["install", "--force", "github:can1357/oh-my-pi@15.10.5"]);
	});

	it("pins npm package installs to the official registry and the checked native package versions", () => {
		const args = buildNpmInstallArgs("16.3.15", "win32-x64");

		expect(args.slice(0, 2)).toEqual(["install", "-g"]);
		expect(args).toContain("--registry=https://registry.npmjs.org/");
		expect(args).toContain("@oh-my-pi/pi-coding-agent@16.3.15");
		expect(args).toContain("@oh-my-pi/pi-natives@16.3.15");
		expect(args).toContain("@oh-my-pi/pi-natives-win32-x64@16.3.15");
	});
});

describe("update-cli npm rename contract", () => {
	it("parses a well-formed omp.rename pointer and rejects malformed ones", () => {
		expect(resolveReleaseRename({ omp: { rename: { package: "@new/omp", natives: "@new/natives" } } })).toEqual({
			pkg: "@new/omp",
			natives: "@new/natives",
		});
		expect(resolveReleaseRename({ omp: { rename: { package: "@new/omp" } } })).toEqual({
			pkg: "@new/omp",
			natives: undefined,
		});
		expect(resolveReleaseRename({ omp: { rename: { package: "" } } })).toBeUndefined();
		expect(resolveReleaseRename({ omp: { rename: "@new/omp" } })).toBeUndefined();
		expect(resolveReleaseRename({ omp: {} })).toBeUndefined();
		expect(resolveReleaseRename(undefined)).toBeUndefined();
	});

	it("installs renamed package names in lock-step, with no old-name leftovers in the argv", () => {
		const packages = { pkg: "@new/omp", natives: "@new/natives" };

		const bunArgs = buildBunInstallArgs("17.0.0", "linux-x64", packages);
		expect(bunArgs).toContain("@new/omp@17.0.0");
		expect(bunArgs).toContain("@new/natives@17.0.0");
		expect(bunArgs).toContain("@new/natives-linux-x64@17.0.0");
		expect(bunArgs.some(arg => arg.startsWith("@oh-my-pi/"))).toBe(false);

		expect(buildNpmInstallArgs("17.0.0", "linux-x64", packages)).toContain("@new/omp@17.0.0");
	});

	it("adds --force to npm argv only for rename migrations so the old package's bin can be clobbered", () => {
		const packages = { pkg: "@new/omp", natives: "@new/natives" };
		expect(buildNpmInstallArgs("17.0.0", "linux-x64", packages, { force: true })).toContain("--force");
		expect(buildNpmInstallArgs("16.3.15", "win32-x64")).not.toContain("--force");
	});

	it("removes the old agent package and its natives companions when both names moved", () => {
		const packages = { pkg: "@new/omp", natives: "@new/natives" };
		expect(buildRenameCleanupPackages(packages, "darwin-arm64")).toEqual([
			"@oh-my-pi/pi-coding-agent",
			"@oh-my-pi/pi-natives",
			"@oh-my-pi/pi-natives-darwin-arm64",
		]);
		expect(buildRenameCleanupPackages(packages, "linux-arm")).toEqual([
			"@oh-my-pi/pi-coding-agent",
			"@oh-my-pi/pi-natives",
		]);
	});

	it("keeps the natives packages on an agent-only rename so cleanup cannot strip the addon the new install pinned", () => {
		const packages = { pkg: "@new/omp", natives: "@oh-my-pi/pi-natives" };
		expect(buildRenameCleanupPackages(packages, "darwin-arm64")).toEqual(["@oh-my-pi/pi-coding-agent"]);
		expect(buildRenameCleanupPackages(packages, "linux-arm")).toEqual(["@oh-my-pi/pi-coding-agent"]);
	});
});

describe("migrateRenamedInstall transaction", () => {
	const release: ReleaseInfo = {
		tag: "v999.1.0",
		version: "999.1.0",
		packages: { pkg: "@new/omp", natives: "@new/natives" },
	};

	function scriptedSteps(script: { install: number[]; removeOld?: number; verify: boolean[] }): {
		steps: RenameMigrationSteps;
		calls: string[];
	} {
		const calls: string[] = [];
		let installs = 0;
		let verifies = 0;
		return {
			calls,
			steps: {
				async install() {
					calls.push("install");
					return script.install[installs++] ?? 0;
				},
				async removeOld() {
					calls.push("removeOld");
					return script.removeOld ?? 0;
				},
				async verify() {
					calls.push("verify");
					return script.verify[verifies++]
						? { ok: true, actual: "999.1.0", path: "/bin/omp" }
						: { ok: false, path: "/bin/omp" };
				},
			},
		};
	}

	it("never touches the old install when the new install fails", async () => {
		vi.spyOn(console, "log").mockImplementation(() => {});
		const { steps, calls } = scriptedSteps({ install: [1], verify: [] });

		await expect(migrateRenamedInstall(release, steps)).rejects.toThrow("left untouched");
		expect(calls).toEqual(["install"]);
	});

	it("installs the new package before removing the old one and verifies the result", async () => {
		vi.spyOn(console, "log").mockImplementation(() => {});
		const { steps, calls } = scriptedSteps({ install: [0], verify: [true] });

		await migrateRenamedInstall(release, steps);
		expect(calls).toEqual(["install", "removeOld", "verify"]);
	});

	it("restores the bin link by reinstalling when old-package removal breaks verification", async () => {
		vi.spyOn(console, "log").mockImplementation(() => {});
		const { steps, calls } = scriptedSteps({ install: [0, 0], verify: [false, true] });

		await migrateRenamedInstall(release, steps);
		expect(calls).toEqual(["install", "removeOld", "verify", "install", "verify"]);
	});

	it("treats old-package removal failure as a warning when the new install verifies", async () => {
		const logs: string[] = [];
		vi.spyOn(console, "log").mockImplementation(message => {
			logs.push(String(message));
		});
		const { steps, calls } = scriptedSteps({ install: [0], removeOld: 1, verify: [true] });

		await migrateRenamedInstall(release, steps);
		expect(calls).toEqual(["install", "removeOld", "verify"]);
		expect(logs.some(line => line.includes("could not remove the old"))).toBe(true);
	});

	it("aborts with a recovery hint when verification still fails after the restore install", async () => {
		vi.spyOn(console, "log").mockImplementation(() => {});
		const { steps, calls } = scriptedSteps({ install: [0, 0], verify: [false, false] });

		await expect(migrateRenamedInstall(release, steps)).rejects.toThrow("curl -fsSL https://omp.sh/install");
		expect(calls).toEqual(["install", "removeOld", "verify", "install", "verify"]);
	});
});

describe("update-cli bun install command", () => {
	it("pins the official npm registry and bypasses the manifest cache so a stale mirror or snapshot cannot mask a freshly published version", () => {
		// Regression: omp queries https://registry.npmjs.org/<pkg>/latest directly.
		// The install MUST hit the same registry, otherwise:
		//   - a lagging mirror (corp proxy, Taobao, …) rejects the version with
		//     `No version matching "X" (but package exists)`,
		//   - or bun's local manifest snapshot does the same when the user's bun
		//     is already pointed at the official registry but its cache predates
		//     the release.
		// See https://github.com/can1357/oh-my-pi/issues/1686.
		const args = buildBunInstallArgs("15.7.6", "linux-x64");
		expect(args.slice(0, 5)).toEqual([
			"install",
			"-g",
			"--no-cache",
			"--registry=https://registry.npmjs.org/",
			"@oh-my-pi/pi-coding-agent@15.7.6",
		]);
	});

	it("pins the native addon core and the platform-specific leaf to the same version so the loader sentinel cannot drift on supported tags", () => {
		// Regression: bun install -g <pkg>@<v> would update only the top-level
		// package, leaving @oh-my-pi/pi-natives and @oh-my-pi/pi-natives-<tag>
		// at their previous version. The next launch then loaded a stale .node
		// file and aborted at validateLoadedBindings with `The .node file on
		// disk is from a different release than this loader`. See
		// https://github.com/can1357/oh-my-pi/issues/1824.
		for (const tag of ["linux-x64", "linux-arm64", "darwin-x64", "darwin-arm64", "win32-x64"]) {
			const args = buildBunInstallArgs("15.9.0", tag);
			expect(args).toContain("@oh-my-pi/pi-natives@15.9.0");
			expect(args).toContain(`@oh-my-pi/pi-natives-${tag}@15.9.0`);
		}
	});

	it("omits the leaf on unsupported platform tags so an EBADPLATFORM swap does not mask the underlying `no matching version` error", () => {
		// Defensive: an unsupported tag (e.g. linux-arm32) still installs the
		// core natives package — which will fail at module load if the platform
		// truly is unsupported — but we never request a leaf the release
		// pipeline doesn't publish, otherwise bun aborts with EBADPLATFORM
		// and hides the real diagnostic from `loadNative`'s aggregated error.
		const args = buildBunInstallArgs("15.9.0", "linux-arm");
		expect(args).toContain("@oh-my-pi/pi-natives@15.9.0");
		expect(args.some(arg => arg.startsWith("@oh-my-pi/pi-natives-"))).toBe(false);
	});

	it("derives global node_modules from supported bun global locations", () => {
		expect(resolveBunGlobalNodeModulesDirFromLocations(path.join("home", ".bun", "bin"), undefined)).toBe(
			path.join("home", ".bun", "install", "global", "node_modules"),
		);
		expect(
			resolveBunGlobalNodeModulesDirFromLocations(undefined, path.join("home", ".bun", "install", "cache")),
		).toBe(path.join("home", ".bun", "install", "global", "node_modules"));
	});
});

describe("update-cli bun cache pruning", () => {
	it("keeps only the newest cached version for filtered global install packages", async () => {
		const dir = await makeTempDir();
		await Bun.write(path.join(dir, "react", "18.3.1@@@1"), "");
		await Bun.write(path.join(dir, "react", "19.2.6@@@1"), "");
		await Bun.write(
			path.join(dir, "react@18.3.1@@@1", "package.json"),
			JSON.stringify({ name: "react", version: "18.3.1" }),
		);
		await Bun.write(
			path.join(dir, "react@19.2.6@@@1", "package.json"),
			JSON.stringify({ name: "react", version: "19.2.6" }),
		);
		await Bun.write(path.join(dir, "@oh-my-pi", "pi-utils", "15.7.6@@@1"), "");
		await Bun.write(path.join(dir, "@oh-my-pi", "pi-utils", "15.8.0@@@1"), "");
		await Bun.write(
			path.join(dir, "@oh-my-pi", "pi-utils@15.7.6@@@1", "package.json"),
			JSON.stringify({ name: "@oh-my-pi/pi-utils", version: "15.7.6" }),
		);
		await Bun.write(
			path.join(dir, "@oh-my-pi", "pi-utils@15.8.0@@@1", "package.json"),
			JSON.stringify({ name: "@oh-my-pi/pi-utils", version: "15.8.0" }),
		);
		await Bun.write(path.join(dir, "chalk", "4.1.2@@@1"), "");
		await Bun.write(path.join(dir, "chalk", "5.6.2@@@1"), "");
		await Bun.write(
			path.join(dir, "chalk@4.1.2@@@1", "package.json"),
			JSON.stringify({ name: "chalk", version: "4.1.2" }),
		);
		await Bun.write(
			path.join(dir, "chalk@5.6.2@@@1", "package.json"),
			JSON.stringify({ name: "chalk", version: "5.6.2" }),
		);

		const result = await pruneBunInstallCache(dir, new Set(["react", "@oh-my-pi/pi-utils"]));

		expect(result).toEqual({ scannedPackages: 2, removedEntries: 4 });
		expect(await Bun.file(path.join(dir, "react", "18.3.1@@@1")).exists()).toBe(false);
		expect(await Bun.file(path.join(dir, "react@18.3.1@@@1", "package.json")).exists()).toBe(false);
		expect(await Bun.file(path.join(dir, "react", "19.2.6@@@1")).exists()).toBe(true);
		expect(await Bun.file(path.join(dir, "react@19.2.6@@@1", "package.json")).exists()).toBe(true);
		expect(await Bun.file(path.join(dir, "@oh-my-pi", "pi-utils", "15.7.6@@@1")).exists()).toBe(false);
		expect(await Bun.file(path.join(dir, "@oh-my-pi", "pi-utils@15.7.6@@@1", "package.json")).exists()).toBe(false);
		expect(await Bun.file(path.join(dir, "@oh-my-pi", "pi-utils", "15.8.0@@@1")).exists()).toBe(true);
		expect(await Bun.file(path.join(dir, "@oh-my-pi", "pi-utils@15.8.0@@@1", "package.json")).exists()).toBe(true);
		expect(await Bun.file(path.join(dir, "chalk", "4.1.2@@@1")).exists()).toBe(true);
		expect(await Bun.file(path.join(dir, "chalk@4.1.2@@@1", "package.json")).exists()).toBe(true);
	});

	it("keeps current registry-qualified marker entries with their materialized package", async () => {
		const dir = await makeTempDir();
		await Bun.write(path.join(dir, "pkg", "1.0.0@@registry.npmjs.org@@@1"), "");
		await Bun.write(
			path.join(dir, "pkg@1.0.0@@registry.npmjs.org@@@1", "package.json"),
			JSON.stringify({ name: "pkg", version: "1.0.0" }),
		);

		const result = await pruneBunInstallCache(dir, new Set(["pkg"]));

		expect(result).toEqual({ scannedPackages: 1, removedEntries: 0 });
		expect(await Bun.file(path.join(dir, "pkg", "1.0.0@@registry.npmjs.org@@@1")).exists()).toBe(true);
		expect(await Bun.file(path.join(dir, "pkg@1.0.0@@registry.npmjs.org@@@1", "package.json")).exists()).toBe(true);
	});

	it("treats a stable release as newer than a matching prerelease", async () => {
		const dir = await makeTempDir();
		await Bun.write(path.join(dir, "pkg", "1.0.0-beta.1@@@1"), "");
		await Bun.write(path.join(dir, "pkg", "1.0.0@@@1"), "");
		await Bun.write(
			path.join(dir, "pkg@1.0.0-beta.1@@@1", "package.json"),
			JSON.stringify({ name: "pkg", version: "1.0.0-beta.1" }),
		);
		await Bun.write(
			path.join(dir, "pkg@1.0.0@@@1", "package.json"),
			JSON.stringify({ name: "pkg", version: "1.0.0" }),
		);

		const result = await pruneBunInstallCache(dir);

		expect(result).toEqual({ scannedPackages: 1, removedEntries: 2 });
		expect(await Bun.file(path.join(dir, "pkg", "1.0.0-beta.1@@@1")).exists()).toBe(false);
		expect(await Bun.file(path.join(dir, "pkg@1.0.0-beta.1@@@1", "package.json")).exists()).toBe(false);
		expect(await Bun.file(path.join(dir, "pkg", "1.0.0@@@1")).exists()).toBe(true);
		expect(await Bun.file(path.join(dir, "pkg@1.0.0@@@1", "package.json")).exists()).toBe(true);
	});

	it("compares numeric version segments without precision loss", async () => {
		const dir = await makeTempDir();
		const older = "1.0.99999999999999999999";
		const newer = "1.0.100000000000000000000";
		await Bun.write(path.join(dir, "pkg", `${older}@@@1`), "");
		await Bun.write(path.join(dir, "pkg", `${newer}@@@1`), "");
		await Bun.write(
			path.join(dir, `pkg@${older}@@@1`, "package.json"),
			JSON.stringify({ name: "pkg", version: older }),
		);
		await Bun.write(
			path.join(dir, `pkg@${newer}@@@1`, "package.json"),
			JSON.stringify({ name: "pkg", version: newer }),
		);

		const result = await pruneBunInstallCache(dir, new Set(["pkg"]));

		expect(result).toEqual({ scannedPackages: 1, removedEntries: 2 });
		expect(await Bun.file(path.join(dir, "pkg", `${older}@@@1`)).exists()).toBe(false);
		expect(await Bun.file(path.join(dir, `pkg@${older}@@@1`, "package.json")).exists()).toBe(false);
		expect(await Bun.file(path.join(dir, "pkg", `${newer}@@@1`)).exists()).toBe(true);
		expect(await Bun.file(path.join(dir, `pkg@${newer}@@@1`, "package.json")).exists()).toBe(true);
	});
});

describe("update-cli release binary integrity", () => {
	const tag = "v17.1.2";
	const binaryName = "omp-linux-x64";
	const url = `https://github.com/can1357/oh-my-pi/releases/download/${tag}/${binaryName}`;
	const content = "verified binary";
	const digest = `sha256:${createHash("sha256").update(content).digest("hex")}`;

	function releaseAsset(overrides: Record<string, unknown> = {}): Record<string, unknown> {
		return {
			tag_name: tag,
			draft: false,
			prerelease: false,
			assets: [
				{
					name: binaryName,
					state: "uploaded",
					size: Buffer.byteLength(content),
					digest,
					browser_download_url: url,
					...overrides,
				},
			],
		};
	}

	it("selects an uploaded asset with a valid SHA-256 digest", () => {
		expect(resolveReleaseBinaryAsset(releaseAsset(), tag, binaryName)).toEqual({
			url,
			size: Buffer.byteLength(content),
			digest,
		});
	});

	it("rejects missing and unsupported release asset digests", () => {
		expect(() => resolveReleaseBinaryAsset(releaseAsset({ digest: null }), tag, binaryName)).toThrow("has no digest");
		expect(() => resolveReleaseBinaryAsset(releaseAsset({ digest: "sha512:abc" }), tag, binaryName)).toThrow(
			"has an unsupported digest",
		);
	});

	it("rejects release metadata that does not identify one exact stable asset", () => {
		expect(() => resolveReleaseBinaryAsset({ ...releaseAsset(), prerelease: true }, tag, binaryName)).toThrow(
			"is not a published stable release",
		);
		expect(() => resolveReleaseBinaryAsset({ ...releaseAsset(), assets: [] }, tag, binaryName)).toThrow(
			`has 0 assets named ${binaryName}`,
		);
		expect(() =>
			resolveReleaseBinaryAsset(
				{ ...releaseAsset(), assets: [releaseAsset().assets, releaseAsset().assets].flat() },
				tag,
				binaryName,
			),
		).toThrow(`has 2 assets named ${binaryName}`);
		expect(() =>
			resolveReleaseBinaryAsset(
				releaseAsset({ browser_download_url: "https://example.com/omp-linux-x64" }),
				tag,
				binaryName,
			),
		).toThrow("has an unexpected download URL");
	});

	it("writes a download only after its size and digest match", async () => {
		const dir = await makeTempDir();
		const targetPath = path.join(dir, binaryName);

		await downloadVerifiedBinary({
			url,
			targetPath,
			expectedSize: Buffer.byteLength(content),
			expectedDigest: digest,
			fetchImpl: async () => new Response(content),
		});

		expect(await Bun.file(targetPath).text()).toBe(content);
		expect((await fs.stat(targetPath)).mode & 0o777).toBe(0o755);
	});

	it("aborts the response stream as soon as it exceeds the expected size", async () => {
		const dir = await makeTempDir();
		const targetPath = path.join(dir, binaryName);
		let pulls = 0;
		const body = new ReadableStream<Uint8Array>(
			{
				pull(controller) {
					pulls++;
					controller.enqueue(new Uint8Array(pulls === 1 ? 2 : 1));
					if (pulls === 2) controller.close();
				},
			},
			{ highWaterMark: 0 },
		);

		await expect(
			downloadVerifiedBinary({
				url,
				targetPath,
				expectedSize: 1,
				expectedDigest: digest,
				fetchImpl: async () => new Response(body),
			}),
		).rejects.toThrow("received at least 2");
		expect(pulls).toBe(1);
		expect(await Bun.file(targetPath).exists()).toBe(false);
	});

	it("wraps a timeout during body streaming with a friendly message", async () => {
		const dir = await makeTempDir();
		const targetPath = path.join(dir, binaryName);
		const body = new ReadableStream<Uint8Array>(
			{
				pull(controller) {
					controller.enqueue(new Uint8Array(1));
					controller.error(new DOMException("The operation timed out.", "TimeoutError"));
				},
			},
			{ highWaterMark: 0 },
		);

		await expect(
			downloadVerifiedBinary({
				url,
				targetPath,
				expectedSize: Buffer.byteLength(content),
				expectedDigest: digest,
				fetchImpl: async () => new Response(body),
			}),
		).rejects.toThrow("Timed out downloading release binary after 15 minutes");
		expect(await Bun.file(targetPath).exists()).toBe(false);
	});

	it("removes downloads whose size or digest does not match", async () => {
		const dir = await makeTempDir();
		const targetPath = path.join(dir, binaryName);
		const fetchImpl = async () => new Response(content);

		await expect(
			downloadVerifiedBinary({
				url,
				targetPath,
				expectedSize: Buffer.byteLength(content) + 1,
				expectedDigest: digest,
				fetchImpl,
			}),
		).rejects.toThrow("size mismatch");
		expect(await Bun.file(targetPath).exists()).toBe(false);

		await expect(
			downloadVerifiedBinary({
				url,
				targetPath,
				expectedSize: Buffer.byteLength(content),
				expectedDigest: `sha256:${createHash("sha256").update("different binary").digest("hex")}`,
				fetchImpl,
			}),
		).rejects.toThrow("digest mismatch");
		expect(await Bun.file(targetPath).exists()).toBe(false);
	});

	it("rejects an altered version-reporting executable before replacing the installed binary", async () => {
		const dir = await makeTempDir();
		const targetPath = path.join(dir, binaryName);
		const installed = "#!/bin/sh\necho omp/17.0.8\n";
		const altered = "#!/bin/sh\necho omp/17.1.2\n";
		const expectedDigest = `sha256:${createHash("sha256")
			.update("x".repeat(Buffer.byteLength(altered)))
			.digest("hex")}`;
		await Bun.write(targetPath, installed);
		await fs.chmod(targetPath, 0o755);

		const metadataAuthorizations: Array<string | null> = [];
		const fetchImpl = async (input: string | URL | Request, init?: RequestInit): Promise<Response> => {
			const requestUrl = String(input);
			if (requestUrl.startsWith("https://api.github.com/")) {
				metadataAuthorizations.push(new Headers(init?.headers).get("Authorization"));
				return new Response(
					JSON.stringify(
						releaseAsset({
							size: Buffer.byteLength(altered),
							digest: expectedDigest,
						}),
					),
				);
			}
			if (requestUrl === url) return new Response(altered);
			throw new Error(`Unexpected request: ${requestUrl}`);
		};

		const previousGitHubToken = Bun.env.GITHUB_TOKEN;
		Bun.env.GITHUB_TOKEN = "test-token";
		try {
			await expect(
				updateViaBinaryAt(targetPath, "17.1.2", {
					binaryName,
					fetchImpl,
				}),
			).rejects.toThrow("digest mismatch");
			expect(metadataAuthorizations).toEqual(["Bearer test-token"]);
			expect(await Bun.file(targetPath).text()).toBe(installed);
			expect((await fs.stat(targetPath)).mode & 0o777).toBe(0o755);
			const newResidue = (await fs.readdir(dir)).filter(name => name.endsWith(".new"));
			expect(newResidue).toEqual([]);
		} finally {
			if (previousGitHubToken === undefined) delete Bun.env.GITHUB_TOKEN;
			else Bun.env.GITHUB_TOKEN = previousGitHubToken;
		}
	});

	it("explains how to authenticate after an anonymous GitHub API rate limit", async () => {
		const dir = await makeTempDir();
		const targetPath = path.join(dir, binaryName);
		const fetchImpl = async () => new Response(null, { status: 403, statusText: "rate limit exceeded" });

		await expect(
			updateViaBinaryAt(targetPath, "17.1.2", {
				binaryName,
				fetchImpl,
				githubToken: "",
			}),
		).rejects.toThrow("retry later or set GITHUB_TOKEN or GH_TOKEN");
		expect(await Bun.file(targetPath).exists()).toBe(false);
	});
});

describe("update-cli binary replacement", () => {
	it("restores the previous binary when the replacement fails verification", async () => {
		const dir = await makeTempDir();
		const targetPath = path.join(dir, "omp");
		const tempPath = `${targetPath}.new`;
		const backupPath = `${targetPath}.bak`;
		await Bun.write(targetPath, "old binary");
		await Bun.write(tempPath, "broken binary");

		await expect(
			replaceBinaryForUpdate({
				targetPath,
				tempPath,
				backupPath,
				expectedVersion: "15.1.8",
				verifyInstalledVersion: async () => ({ ok: false, path: targetPath }),
			}),
		).rejects.toThrow("restored previous omp binary");

		expect(await Bun.file(targetPath).text()).toBe("old binary");
		expect(await Bun.file(tempPath).exists()).toBe(false);
		expect(await Bun.file(backupPath).exists()).toBe(false);
	});

	it("keeps the replacement only after it reports the expected version", async () => {
		const dir = await makeTempDir();
		const targetPath = path.join(dir, "omp");
		const tempPath = `${targetPath}.new`;
		const backupPath = `${targetPath}.bak`;
		await Bun.write(targetPath, "old binary");
		await Bun.write(tempPath, "new binary");

		await replaceBinaryForUpdate({
			targetPath,
			tempPath,
			backupPath,
			expectedVersion: "15.1.8",
			verifyInstalledVersion: async () => ({ ok: true, actual: "15.1.8", path: targetPath }),
		});

		expect(await Bun.file(targetPath).text()).toBe("new binary");
		expect(await Bun.file(tempPath).exists()).toBe(false);
		expect(await Bun.file(backupPath).exists()).toBe(false);
	});
});

describe("update-cli binary replacement on locked backups", () => {
	it("treats an EPERM on backup cleanup as a successful, completed update", async () => {
		// Regression: on Windows the binary moved aside during the swap is still
		// the running process image, so unlinking it throws EPERM. That cleanup
		// failure must not turn a verified swap into "Update failed" (issue #845).
		const dir = await makeTempDir();
		const targetPath = path.join(dir, "omp.exe");
		const tempPath = `${targetPath}.new`;
		const backupPath = `${targetPath}.1700000000000.4242.bak`;
		await Bun.write(targetPath, "old binary");
		await Bun.write(tempPath, "new binary");

		const realUnlink = nodeFs.promises.unlink.bind(nodeFs.promises);
		const spy = spyOn(nodeFs.promises, "unlink").mockImplementation(async (p: nodeFs.PathLike) => {
			if (String(p) === backupPath) {
				const err = new Error(`EPERM: operation not permitted, unlink '${p}'`) as NodeJS.ErrnoException;
				err.code = "EPERM";
				throw err;
			}
			return realUnlink(p);
		});
		try {
			const result = await replaceBinaryForUpdate({
				targetPath,
				tempPath,
				backupPath,
				expectedVersion: "15.1.8",
				verifyInstalledVersion: async () => ({ ok: true, actual: "15.1.8", path: targetPath }),
			});
			expect(result.ok).toBe(true);
		} finally {
			spy.mockRestore();
		}

		// New binary is installed and the temp consumed even though the locked
		// backup survives; the next run's sweep reclaims it once it is unlocked.
		expect(await Bun.file(targetPath).text()).toBe("new binary");
		expect(await Bun.file(tempPath).exists()).toBe(false);
		expect(await Bun.file(backupPath).text()).toBe("old binary");
	});
});

describe("update-cli stale update artifact sweep", () => {
	it("reclaims timestamped and legacy backups and orphaned temps while sparing in-progress temps and unrelated files", async () => {
		const dir = await makeTempDir();
		const targetPath = path.join(dir, "omp.exe");
		await Bun.write(targetPath, "current binary");
		await Bun.write(`${targetPath}.bak`, "legacy backup");
		await Bun.write(`${targetPath}.1700000000000.4242.bak`, "timestamped backup");
		await Bun.write(`${targetPath}.1800000000000.99.bak`, "another backup");
		// Orphaned temp files from a hard-killed download: reaped once older than
		// the download window. Legacy fixed name and timestamped name both count.
		const stale = new Date(Date.now() - 60 * 60 * 1000);
		await Bun.write(`${targetPath}.new`, "legacy temp");
		await fs.utimes(`${targetPath}.new`, stale, stale);
		await Bun.write(`${targetPath}.1700000000000.4242.new`, "timestamped temp");
		await fs.utimes(`${targetPath}.1700000000000.4242.new`, stale, stale);
		// Must survive: a fresh temp still belongs to a concurrent, in-progress
		// download (unique per attempt), plus foreign basenames and non-numeric
		// middle segments.
		await Bun.write(`${targetPath}.9999999999999.7.new`, "in-progress temp");
		await Bun.write(path.join(dir, "notes.bak"), "keep me");
		await Bun.write(`${targetPath}.config.bak`, "keep me too");
		await Bun.write(`${targetPath}.config.new`, "keep me three");

		await sweepStaleUpdateArtifacts(targetPath);

		expect(await Bun.file(targetPath).exists()).toBe(true);
		expect(await Bun.file(`${targetPath}.bak`).exists()).toBe(false);
		expect(await Bun.file(`${targetPath}.1700000000000.4242.bak`).exists()).toBe(false);
		expect(await Bun.file(`${targetPath}.1800000000000.99.bak`).exists()).toBe(false);
		expect(await Bun.file(`${targetPath}.new`).exists()).toBe(false);
		expect(await Bun.file(`${targetPath}.1700000000000.4242.new`).exists()).toBe(false);
		expect(await Bun.file(`${targetPath}.9999999999999.7.new`).exists()).toBe(true);
		expect(await Bun.file(path.join(dir, "notes.bak")).exists()).toBe(true);
		expect(await Bun.file(`${targetPath}.config.bak`).exists()).toBe(true);
		expect(await Bun.file(`${targetPath}.config.new`).exists()).toBe(true);
	});
});

describe("update-cli binary-only release gating", () => {
	it("honors an explicit omp.dist field from the registry manifest", () => {
		expect(resolveReleaseDist({ omp: { dist: "binary" } })).toBe("binary");
		expect(resolveReleaseDist({ omp: { dist: "npm" } })).toBe("npm");
	});

	it("treats unknown dist values as binary-only", () => {
		expect(resolveReleaseDist({ omp: { dist: "cargo" } })).toBe("binary");
	});

	it("returns undefined when the manifest carries no dist field", () => {
		expect(resolveReleaseDist({ version: "1.2.3" })).toBeUndefined();
		expect(resolveReleaseDist({ omp: {} })).toBeUndefined();
		expect(resolveReleaseDist(undefined)).toBeUndefined();
	});

	it("forces binary updates when dist is binary regardless of version", () => {
		expect(shouldForceBinaryUpdate({ version: "1.2.3", dist: "binary" }, "1.2.2")).toBe(true);
	});

	it("allows package-manager updates across majors when dist is explicitly npm", () => {
		expect(shouldForceBinaryUpdate({ version: "2.0.0", dist: "npm" }, "1.9.0")).toBe(false);
	});

	it("forces binary updates on a major bump without a dist field", () => {
		expect(shouldForceBinaryUpdate({ version: "2.0.0" }, "1.9.0")).toBe(true);
		expect(shouldForceBinaryUpdate({ version: "2.0.0-rc.1" }, "1.9.0")).toBe(true);
	});

	it("keeps package-manager updates within the same major and on downgrades", () => {
		expect(shouldForceBinaryUpdate({ version: "1.10.0" }, "1.9.0")).toBe(false);
		expect(shouldForceBinaryUpdate({ version: "1.0.0" }, "2.0.0")).toBe(false);
	});
});

describe("update-cli script-shim takeover", () => {
	const version = "18.0.0";
	const binaryName = "omp-windows-x64.exe";
	const url = `https://github.com/can1357/oh-my-pi/releases/download/v${version}/${binaryName}`;

	function makeFetch(content: string): (input: string | URL | Request) => Promise<Response> {
		const digest = `sha256:${createHash("sha256").update(content).digest("hex")}`;
		return async (input: string | URL | Request): Promise<Response> => {
			const requestUrl = String(input);
			if (requestUrl.startsWith("https://api.github.com/")) {
				return new Response(
					JSON.stringify({
						tag_name: `v${version}`,
						draft: false,
						prerelease: false,
						assets: [
							{
								name: binaryName,
								state: "uploaded",
								size: Buffer.byteLength(content),
								digest,
								browser_download_url: url,
							},
						],
					}),
				);
			}
			if (requestUrl === url) return new Response(content);
			throw new Error(`Unexpected request: ${requestUrl}`);
		};
	}

	const shims: Record<string, string> = {
		omp: "#!/bin/sh\nnode omp.js\n",
		"omp.cmd": "@node omp.js %*\n",
		"omp.ps1": "node omp.js @args\n",
	};

	async function writeShims(dir: string): Promise<void> {
		for (const name in shims) {
			await Bun.write(path.join(dir, name), shims[name]);
		}
	}

	it("installs omp.exe beside the shims and retires them", async () => {
		const dir = await makeTempDir();
		await writeShims(dir);
		// Real executable, no injected verifier: the takeover must verify the
		// exe by explicit path — $which cached the shim path before it was
		// renamed away, so a PATH re-resolution would fail here.
		const exe = `#!/bin/sh\necho omp/${version}\n`;

		await updateViaShimTakeover(path.join(dir, "omp.cmd"), version, {
			binaryName,
			fetchImpl: makeFetch(exe),
			githubToken: "test-token",
		});

		expect(await Bun.file(path.join(dir, "omp.exe")).text()).toBe(exe);
		for (const name in shims) {
			expect(await Bun.file(path.join(dir, name)).exists()).toBe(false);
		}
		const residue = (await fs.readdir(dir)).filter(name => name.endsWith(".bak") || name.endsWith(".new"));
		expect(residue).toEqual([]);
	});

	it("restores the shims and removes the exe when the exe reports the wrong version", async () => {
		const dir = await makeTempDir();
		await writeShims(dir);
		// Executable runs but reports the previous version -> full rollback.
		const exe = "#!/bin/sh\necho omp/17.2.12\n";

		await expect(
			updateViaShimTakeover(path.join(dir, "omp.cmd"), version, {
				binaryName,
				fetchImpl: makeFetch(exe),
				githubToken: "test-token",
			}),
		).rejects.toThrow(/still reports 17\.2\.12 \(expected 18\.0\.0\); restored previous omp launcher/);

		expect(await Bun.file(path.join(dir, "omp.exe")).exists()).toBe(false);
		for (const name in shims) {
			expect(await Bun.file(path.join(dir, name)).text()).toBe(shims[name]);
		}
		const residue = (await fs.readdir(dir)).filter(name => name.endsWith(".bak") || name.endsWith(".new"));
		expect(residue).toEqual([]);
	});

	function renameLockingPs1(): Mock<typeof nodeFs.promises.rename> {
		const realRename = nodeFs.promises.rename;
		return spyOn(nodeFs.promises, "rename").mockImplementation(async (from, to) => {
			if (path.basename(String(from)) === "omp.ps1") {
				throw Object.assign(new Error("EPERM: file is locked"), { code: "EPERM" });
			}
			return await realRename(from, to);
		});
	}

	it("rewrites an immovable precedence-winning shim as a forwarder to the exe", async () => {
		const dir = await makeTempDir();
		await writeShims(dir);
		const exe = `#!/bin/sh\necho omp/${version}\n`;
		const renameSpy = renameLockingPs1();
		try {
			await updateViaShimTakeover(path.join(dir, "omp.cmd"), version, {
				binaryName,
				fetchImpl: makeFetch(exe),
				githubToken: "test-token",
			});
		} finally {
			renameSpy.mockRestore();
		}

		expect(await Bun.file(path.join(dir, "omp.exe")).text()).toBe(exe);
		expect(await Bun.file(path.join(dir, "omp")).exists()).toBe(false);
		expect(await Bun.file(path.join(dir, "omp.cmd")).exists()).toBe(false);
		// PowerShell resolves .ps1 before .exe: the locked shim must now exec
		// the new binary instead of keeping its old body.
		expect(await Bun.file(path.join(dir, "omp.ps1")).text()).toContain('& "$PSScriptRoot\\omp.exe" @args');
	});

	it("restores a forwarded shim's original body when verification fails", async () => {
		const dir = await makeTempDir();
		await writeShims(dir);
		const exe = "#!/bin/sh\necho omp/17.2.12\n";
		const renameSpy = renameLockingPs1();
		try {
			await expect(
				updateViaShimTakeover(path.join(dir, "omp.cmd"), version, {
					binaryName,
					fetchImpl: makeFetch(exe),
					githubToken: "test-token",
				}),
			).rejects.toThrow("restored previous omp launcher");
		} finally {
			renameSpy.mockRestore();
		}

		expect(await Bun.file(path.join(dir, "omp.exe")).exists()).toBe(false);
		for (const name in shims) {
			expect(await Bun.file(path.join(dir, name)).text()).toBe(shims[name]);
		}
	});
});

describe("update-cli concurrent binary updates", () => {
	const version = "999.0.0";
	const binaryName = "omp-linux-x64";
	const url = `https://github.com/can1357/oh-my-pi/releases/download/v${version}/${binaryName}`;
	const payload = Buffer.alloc(2048, 0x41);
	const digest = `sha256:${createHash("sha256").update(payload).digest("hex")}`;

	function metadata(): Response {
		return Response.json({
			tag_name: `v${version}`,
			draft: false,
			prerelease: false,
			assets: [{ name: binaryName, state: "uploaded", size: payload.byteLength, digest, browser_download_url: url }],
		});
	}

	const fastFetch = async (input: string | URL | Request): Promise<Response> => {
		const requestUrl = String(input);
		if (requestUrl.startsWith("https://api.github.com/")) return metadata();
		if (requestUrl === url) return new Response(payload);
		throw new Error(`Unexpected request: ${requestUrl}`);
	};

	const verify = async () => ({ ok: true, actual: version });

	async function prepare(): Promise<{ dir: string; targetPath: string }> {
		const loadedTheme = await getThemeByName("dark");
		if (!loadedTheme) throw new Error("theme unavailable");
		setThemeInstance(loadedTheme);
		vi.spyOn(console, "log").mockImplementation(() => {});
		const dir = await makeTempDir();
		const targetPath = path.join(dir, "omp");
		await Bun.write(targetPath, "old binary");
		return { dir, targetPath };
	}

	// Regression for #8434: two overlapping `omp update` runs must not share a
	// temp path. Run A downloads slowly and only finishes after run B has fully
	// installed. With the old fixed `<binary>.new` temp name, B's pre-download
	// unlink deleted A's temp file, so A's chmod failed with ENOENT even though
	// its size + digest passed. Unique temp paths keep the two runs independent.
	it("lets an overlapping slow run install after a fast run completes, instead of failing chmod with ENOENT", async () => {
		const { dir, targetPath } = await prepare();

		const aWroteFirstChunk = Promise.withResolvers<void>();
		const letAFinish = Promise.withResolvers<void>();
		const slowFetch = async (input: string | URL | Request): Promise<Response> => {
			const requestUrl = String(input);
			if (requestUrl.startsWith("https://api.github.com/")) return metadata();
			if (requestUrl === url) {
				return new Response(
					new ReadableStream<Uint8Array>({
						async start(controller) {
							controller.enqueue(payload.subarray(0, 1024));
							aWroteFirstChunk.resolve();
							await letAFinish.promise;
							controller.enqueue(payload.subarray(1024));
							controller.close();
						},
					}),
				);
			}
			throw new Error(`Unexpected request: ${requestUrl}`);
		};

		const runA = updateViaBinaryAt(targetPath, version, {
			binaryName,
			fetchImpl: slowFetch,
			verifyInstalledVersion: verify,
		});
		await aWroteFirstChunk.promise;
		await updateViaBinaryAt(targetPath, version, {
			binaryName,
			fetchImpl: fastFetch,
			verifyInstalledVersion: verify,
		});
		letAFinish.resolve();
		await runA;

		expect(await Bun.file(targetPath).bytes()).toEqual(new Uint8Array(payload));
		const residue = (await fs.readdir(dir)).filter(name => name.endsWith(".new"));
		expect(residue).toEqual([]);
	});

	// Regression: a failed verification must still roll back its own backup even
	// when another update completes while it is held. The per-target lock
	// serializes the swap + sweep, so the concurrent run's sweep cannot reclaim
	// the live backup before the rollback renames it back.
	it("rolls back its backup when verification fails while another update runs", async () => {
		const { dir, targetPath } = await prepare();

		const enteredVerify = Promise.withResolvers<void>();
		const releaseVerify = Promise.withResolvers<void>();
		const failingVerify = async () => {
			enteredVerify.resolve();
			await releaseVerify.promise;
			return { ok: false, actual: "0.0.0", path: targetPath };
		};

		const runA = updateViaBinaryAt(targetPath, version, {
			binaryName,
			fetchImpl: fastFetch,
			verifyInstalledVersion: failingVerify,
		});
		await enteredVerify.promise;
		const runB = updateViaBinaryAt(targetPath, version, {
			binaryName,
			fetchImpl: fastFetch,
			verifyInstalledVersion: verify,
		});
		releaseVerify.resolve();
		await expect(runA).rejects.toThrow(/still reports 0\.0\.0 \(expected 999\.0\.0\)/);
		await runB;

		expect(await Bun.file(targetPath).bytes()).toEqual(new Uint8Array(payload));
		const residue = (await fs.readdir(dir)).filter(name => name.endsWith(".bak") || name.endsWith(".new"));
		expect(residue).toEqual([]);
	});
});